Convert object to byte[] in Java

This article shows how to convert an object to byte[] or byte array and vice versa in Java. 1. Convert an object to byte[] The below example show how to use ByteArrayOutputStream and ObjectOutputStream to convert an object to byte[]. // Convert object to byte[] public static byte[] convertObjectToBytes(Object obj) { ByteArrayOutputStream boas = new …

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How to generate serialVersionUID in Intellij IDEA

In IntelliJ IDEA, we need to enable this auto-generate serialVersionUID option manually. P.S Tested with IntelliJ IDEA 2019.3.4, it should work the same in other versions. Intellij IDEA Settings File -> Settings -> Editor -> Inspections -> Java -> Serialization issues: Find serialization class without serialVersionUID and check it. Back to the editor, clicks on …

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Java Serialization and Deserialization Examples

In Java, Serialization means converting Java objects into a byte stream; Deserialization means converting the serialized object’s byte stream back to the original Java object. Table of contents. 1. Hello World Java Serialization 2. java.io.NotSerializableException 3. What is serialVersionUID? 4. What is transient? 5. Serialize Object to File 6. Why need Serialization in Java? 7. …

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Java – What is transient fields?

In Java, transient fields are excluded in the serialization process. In short, when we save an object into a file (serialization), all transient fields are ignored. 1. POJO + transient Review the following Person class; the salary field is transient. public class Person implements Serializable { private static final long serialVersionUID = 1L; private String …

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How to read and write Java object to a file

Java object Serialization is an API provided by Java Library stack as a means to serialize Java objects. Serialization is a process to convert objects into a writable byte stream. Once converted into a byte-stream, these objects can be written to a file. The reverse process of this is called de-serialization. A Java object is …

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Java – What is serialVersionUID

In Java, serialVersionUID is something like version control, assure both serialized and deserialized objects are using the compatible class. For example, if an object saved into a file (Serialization) with serialVersionUID=1L, when we convert the file back to an object (Derialization), we must use the same serialVersionUID=1L, otherwise an InvalidClassException is thrown. Terminal Exception in …

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Java – How to generate serialVersionUID

This article shows you a few ways to generate the serialVersionUID for serialization class. 1. serialver JDK has a built-in command serialver to generate a serialVersionUID automatically. In this example, we use serialver to generate a serialVersionUID for an Address class. Terminal $ serialver Address Address: static final long serialVersionUID = -687991492884005033L; 2. Eclispe IDE …

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How to read an object from file in Java (ObjectInputStream)

This example shows how to use ObjectInputStream to read a serialized object from a file in Java, aka Deserialization. public static Object readObjectFromFile(File file) throws IOException, ClassNotFoundException { Object result = null; try (FileInputStream fis = new FileInputStream(file); ObjectInputStream ois = new ObjectInputStream(fis)) { result = ois.readObject(); } return result; } // Convert byte[] to …

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How to write an object to file in Java (ObjectOutputStream)

This example shows how to use ObjectOutputStream to write objects to a file in Java, aka Serialization. public static void writeObjectToFile(Person obj, File file) throws IOException { try (FileOutputStream fos = new FileOutputStream(file); ObjectOutputStream oos = new ObjectOutputStream(fos)) { oos.writeObject(obj); oos.flush(); } } Note More Java Serialization and Deserialization examples 1. Java object We can …

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